• The Transactions of the Korean Institute of Power Electronics
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• v.26 no.3
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• pp.227-236
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• 2021

This research proposes a modeling and controller design of a three-level boost (TLB) converter for the implementation of maximum power point tracking (MPPT) in the photovoltaic power conditioning system (PCS). Contrary to the output voltage control of the conventional controller, the Photovoltaic PCS requires an input voltage controller for MPPT operation. A TLB converter has the advantage of decreasing the inductor size and increasing efficiency compared with the existing booster converter. However, an optimal controller is difficult to design due to the complexity of the TLB operations, which have two operational modes on the duty ratio boundary of 0.5. Therefore, the unified linear model equations of the TLB converters, which can be applicable to both operational modes, are derived using linearized solar cell expressions. Furthermore, the transfer functions are obtained for the controller design. The MPPT voltage controller is designed using MATLAB SISOTOOL. In addition, a controller for capacitor voltage unbalancing is described and designed. The simulations and experimental verifications are conducted to verify the effectiveness of the small-signal analysis and control system design.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.21 no.6
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• pp.101-108
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• 2011

The turnover rate of information security professionals in Korea is over 10% and turnover into non-information security fields accounts for over 50% of all the turnovers [1]. It is not only important to recruit a new quality workforce, but also to make the current workforce perform satisfactorily, to improve their performance, and eventually to attain information security objectives. This study proposes a Markov chain model for the turnover process of information security professionals and forecasts the job duty composition of information security professionals. The results of this study can be applied to secure the justification of government policies for the promotion of information security professionals.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.3
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• pp.235-243
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• 2022

To help the industry, outsourcing was found to be the most efficient method. An extensive literature analysis was done to assess the macroeconomic factors associated with outsourcing to supplement the anxious parties' decision-making process with evidence-based comprehensive tools. As a theoretical framework for evaluating these issues, transaction cost economies and resource-based perspective theories are investigated. Outsourcing is proven to be a result of energy crises and political instability. The advantages of outsourcing assist major industries in the economy. To discover the key drivers behind outsourcing, we used the vector autoregressive (VAR model) and step-wise regression techniques for the period 1992 to 2016. This research adds to the literature in that it not only explains the energy issue but also discusses the dilemma of political instability in the country in the context of outsourcing. The findings indicate that labor cost and export tendency have a positive impact on outsourcing strategy, which confirms the study's third and fourth hypotheses. Customs tax, inflation, and the unemployment rate, on the other hand, have a negative impact on textile outsourcing in Pakistan, according to the study's fifth, sixth, and seventh hypotheses.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.1
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• pp.1-9
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• 2015

To satisfy stricter $NO_X$ emission regulations for light- and heavy-duty diesel vehicles, a control algorithm needs to be developed based on a selective catalytic reaction (SCR) dynamics model for chemical reactions. This paper presents the development and validation of a SCR dynamics model through test rig experiments and MATLAB simulations. A nonlinear state space model is proposed based on the mass conservation law of chemical reactions in the SCR dynamics model. Experiments were performed on a test rig to evaluate the effects of the $NO_X$ and $NH_3$ concentrations, gas temperature, and space velocity on the $NO_X$ conversion efficiency for the urea-SCR system. The parameter values of the proposed SCR model were identified using the experimental datasets. Finally, a control-oriented model for an SCR system was developed and validated from the experimental data in a MATLAB simulation. The results of this study should contribute toward developing a closed-loop control strategy for $NO_X$ and $NH_3$ slip reduction in the urea-SCR system for an actual engine test bench.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4523-4535
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• 2012

As a way to popularize Karatedo, a curriculum for developing excellent trainers is needed. For that, DACUM was used to specifically look into the field of duty and work that a Karatedo trainer should have, and the purpose of this study is to present fundamental data necessary for developing and organizing the curriculum of cultivating Karatedo and create a useful material that can contribute to improve Karatedo trainers' performances who are working on site. A survey using Likert scale's 7 stages was conducted on DACUM meeting data, 28 managers and 108 trainers. Based on the collected data, this study had a test in order to solve the presented subject using DACUM method and SPSS WIN Ver. 14.0. This core work through the requirements analysis process. And karate leaders the necessary knowledge, skills, and tools, and attitude analysis was carried out to perform the tasks of each. Knowledge, skills, tools and attitude for each task, toward the results of the analysis were 47 core tasks. 167 knowledge items, function 143 items, the tool 60 items, 16 attitude items reclassified a total of 18 subjects were derived. The configuration of the karate leader training program curriculum model 'Karate practical expert area', 'theory karate expert area', 'Karate gym business area experts' was composed. Basic process of how it works Step 1, Step 2 integration process, replenishment process intensified Step 3 was composed.

• Korean Journal of Occupational Health Nursing
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• v.14 no.2
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• pp.93-107
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• 2005

Purpose: The purpose of this study is to identify the trends of studies on work-related musculoskeletal disorder and to suggest the direction of future research. Method: 144 research thesis for a degree on work-related musculoskeletal disorder were systematic reviewed and published from Jan. 1990 to Mar. 2005. The analyzed using descriptive statistics, an actual number, percentage. Result: As its result the work-related musculoskeletal disorder research which is announced from domestic the doctorate dissertation at the 2004 year 42 the most many 144 dissertation middle most to be 129 in master degree dissertation was 15 in Ph D degree. Dissertation contents character the contents against the result relation that it analyzes especially and a condition and an obstacle was many most at 84. Research plan in most description investigation research 121 the dissertation field to be the especially public health (hygiene, industry and environment) at this 57 most many research object person distribution manufacturing industry in the research object one dissertation was many most at the 40. The tools which are used in each measurement in the question tool which it uses most the question price of land which uses the condition investigation ticket which it made from the NIOSH and the ANSI most many 33, the hazard which analyzes a work attitude in the tool which it uses the RULA was many most at 14. In the stress test tool social psychological healthy measurement PWI (Psychological Wellbeing Index) the dissertation which uses the Job Strain of the Karasek Model to be many most at 19 PWI (Psychological Wellbeing Index) 7 easy use. Work-related musculoskeletal disorder measurement hazard in physiological index and the machinery and tools which it uses there were 9 researches to use an electromyogram most plentifully. With the effect goes to a work-related musculoskeletal disorder they are 33 where the age is many most from general quality. From healthy act with the relation of smoking the year to be many from 16 dissertations. Work of the corpse an attitude (the attitude which is inappropriate) with 5 and the work market the work burglar is many most at 9, the society-support of 36 where the stress is many psychologically most, the stress and service also the most many duty discretion (authority and autonomy) is 6 at the duty demand boat song 9. The service career to be many is 22 of extraordinarily with relation of service. Conclusion: It is recommended the research which it sees being limited in only domestic thesis for a degree the international comparative study to become accomplished. It comes to think with the fact that it will be necessary to make the protocol which it conforms in the civil official guide the test researches for the protocol or arbitration program which is standardized are necessary. Prevention and the civil official of work relation bones and sinews standing total disease hazard scientific base one program is necessary with base.

• Journal of Distribution Science
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• v.15 no.12
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• pp.85-94
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• 2017

Purpose - Owing to economic development and rapid globalization, the number of people traveling abroad has increased dramatically in recent years. For instance, according to data from World Tourism Organization, approximately 1,724 million tourists traveled abroad in 2016. This phenomenon has resulted in a change for domestic markets, as they no longer serve only domestic customers but also serve foreign customers as well. Therefore, intercultural service encounters between services providers and customers from diverse cultural backgrounds are becoming more frequent. Especially in the field of retailing, salesperson's customer oriented selling behavior is particularly important for the successful interactions. However, it is hard to find some factors that can improve salesperson's customer oriented selling behavior in intercultural sales encounters. Research design, data, and methodology - A quantitative survey methodology was utilized to collect data on 312 salespeople at duty-free shops located on Jeju Island, Korea. As a tourism-based region, Jeju Island has attracted a large number of foreign tourists since being designated as an international free city in 2002. Owing to this phenomenon, intercultural sales encounters between salespersons and customers from different cultures have become commonplace. Compared to other salespeople, salespeople working in duty-free shops have more frequent intercultural interactions, as over 90% of their total customers are from foreign countries. Additionally, regular professional training programs for salespeople help cultivate cultural intelligence. Data analysis was conducted using SPSS 20. Results - This paper explores the role of empathy and cultural intelligence in intercultural sales encounters using a theoretical model incorporating the causal relationships between empathy(cognitive empathy and emotional empathy) and customer oriented selling behavior, as well as the moderating effects of cultural intelligence in these relationships. Conclusions - This study is almost the first to explore the influence of empathy and cultural intelligence in intercultural sales encounters. Thus, this study provides a meaningful contribution to the application of empathy and cultural intelligence in the retailing field and will draw the attention of personal distribution practicers and researchers to the importance of empathy and cultural intelligence. Additionally, this study has useful managerial implications for employee selection, training, and development in retailing firms engaged in intercultural sales encounters.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.3
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• pp.171-178
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• 2014

From now on, in order to meet more stringer diesel emission standard, diesel vehicle should be equipped with emission after-treatment devices as NOx reduction catalyst and particulate filters. Urea-SCR is being developed as the most efficient method of reducing NOx emissions in the after-treatment devices of diesel engines, and recent studies have begun to mount the urea-SCR device for diesel passenger cars and light duty vehicles. That is because their operational characteristics are quite different from heavy duty vehicles, urea solution injection should be changed with other conditions. Therefore, the number and diameter of the nozzle, injection directions, mounting positions in front of the catalytic converter are important design factors. In this study, major design parameters concerning urea solution injection in front of SCR are optimized by using a CFD analysis and Taguchi method. The computational prediction of internal flow and spray characteristics in front of SCR was carried out by using STAR-CCM+7.06 code that used to evaluate $NH_3$ uniformity index($NH_3$ UI). The design parameters are optimized by using the $L_{16}$ orthogonal array and small-the-better characteristics of the Taguchi method. As a result, the optimal values are confirmed to be valid in 95% confidence and 5% significance level through analysis of variance(ANOVA). The compared maximize $NH_3$ UI and activation time($NH_3$ UI 0.82) are numerically confirmed that the optimal model provides better conversion efficiency of $NH_3$. In addition, we propose a method to minimize wall-wetting around the urea injector in order to prevent injector blocks caused by solid urea loading. Consequently, the thickness reduction of fluid film in front of mixer is numerically confirmed through the mounting mixer and correcting injection direction by using the trial and error method.

• Journal of Society of Preventive Korean Medicine
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• v.21 no.3
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• pp.11-18
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• 2017

Objectives : In an effort to suggest a developmental plan of Traditional Korean Medicine health promotion project(TKM-HPP), this study was conducted to identify the problems experienced by public health Traditional Korean Medicine(PH-TKM) doctors in duty and to analyze successful cases of the health promotion project. Methods : Two PH-TKM doctors in duty at the Public Health Centre branch and Public Health Centre respectively, and one TKM doctor in charge of Public Health Centre participated in the in-depth interview. The research procedure was as follows; 1) inform study objectives and interview questions to participants, 2) in-depth interview with semi-structured questions, and 3) post-confirmation and verification. The interview was recorded and transcripted. In-depth interview was composed of 6 subsections: 1) Introducing participants and share purpose of interview, 2) Confirmation of the job status and difficulty of public health centre, 3) Reflecting and sharing experiences of public health clinic job performance cases, 4) Current status and improvement needs of TKM-HPP, 5) Discussions on improvement of TKM-HPP in public health center, 6) Sharing and reconfirmation of interview results. Thematic analysis was conducted from the narratives. Results : The study showed that; 1) the support from the local government was critical for the successful TKM-HPP and participation of the PH-TKMs; 2) the major problems experienced by PH-TKMs were lack of training for TKM-HPP in the field and lack of knowledge at local government level; 3) the suggestions to provide PH-TKMs with manual to educate residents effectively and redefine roles of PH-TKMs in the project. It also suggests that TKM-HPP model should be developed by the district in a way of reflecting regional characteristics. Conclusions : Firstly, more efforts should be made on the projects rather than medical treatment in public health centers, except for areas where medical institutions are scarce. Secondly, in order to facilitate participation of PH-TKM doctors, each local office should reduce medical care and increase efforts related with projects. Thirdly, the institution has to develop feasible TKM-HPP plans that can be carried out by PH-TKMs by the manual. Lastly, pre-training should be provided to PH-TKMs to understand contents of TKM-HPP related to public health centre work before the placement.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5501-5507
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• 2015

This study seeks to identify the duties and tasks of a social welfare worker when developing a combined death education program for welfare workers using DACUM method. The program would adopt both a medical and humanistic perspective that can be applied to real life. The study period was between March 2 to March 10, 2015. The study was conducted on eight DACUM committee members who are professors in the field of healthcare or humanities and social sciences. Their medical, humanistic and social viewpoints were investigated. The results show that the focus of the education needs to be on 'the acceptance and understanding of death' and 'healing the stress from loss and suicide prevention'as tasks under the duty of 'loss and mourning'. The tasks for the duty 'the need for death education'were identified as 'death in traditional society and death in contemporary society' as well as 'understanding of issues related to death'. The results show that there is a need to develop death education programs that emphasize healing for the acceptance and understanding of death from a humanistic perspective.